INTRODUCTION. 25 
to be numerous as a class or particularly well preserved, many appearing in the 
condition of casts. The ‘ Oolite Marl” yields a fairly respectable list of Gastero- 
poda, and some of these are really in good condition, well preserved in fine white 
calcite, so as to constitute a valuable acquisition to the cabinet. Mr. Brodie also 
has some good specimens of Gasteropoda, mostly small, from the freestones, which 
bear some resemblance to the Fauna and facies of the Lincolnshire Limestone. 
On the whole, however, the Cotteswold area of the Inferior Oolite is rather dis- 
appointing, and if it were not for the abundance of Nerinea on certain lines 
in the “Oolite Marl’ and associated beds, and the occurrence of this 
genus to a less extent in the “ Pea-grit” below and the ‘“ Clypeus-grit”’ 
above, the ground would be somewhat poor hunting for those in search of Gas- 
teropods. It has generally been held, and I think justly, that these shells are in 
some way associated with coral growth, and this seems all the more probable when 
we bear in mind that the No. 1, or Dorset district, notwithstanding its wealth of 
Gasteropods, has not yielded a single Nerinea to collectors, so far as my experience 
goes. The genus Nerinea has been traced as far as Radstock in the uppermost 
beds of the Inferior Oolite, but south of the Mendips it seems to be entirely absent, 
and this is also the case with beds on the same horizon in Normandy. 
Tn the East Midland district, if we except the development of certain estuarine 
and ferruginous deposits, the Inferior Oolite is still mainly calcareous. The 
Lincolnshire Limestone is remarkably devoid of Cephalopoda, and the facies, where 
any abundance of fossils occurs, is described by Professor Judd as partly coralline 
and partly shelly. With few exceptions the Gasteropoda are small, but excessively 
numerous in certain places, and the genus Nerina is well represented throughout. 
It would be difficult to show a greater contrast than that which exists between the 
Lincolnshire Limestone, with its white Oolite, small shells, and total absence of 
Ammonites, and the Dorsetshire ironshot Oolites, so full of Ammonites and 
Belemnites that Mr. H. B. Woodward declares the entire Inferior Oolite of that 
region might be called a Cephalopoda-bed.’ It is probable that the greater part of 
the Lincolnshire Limestone belongs to the Lower Division, though matters are more 
obscure here than in the south-west. The facies and general appearance of the 
upper beds of the Lincolnshire Limestone at Weldon, Wansford, Barnack, &c., has 
a strong resemblance to the Great Oolite as developed at Minchinhampton and 
elsewhere, but possibly this resemblance is in part superficial, and it may be that 
the freestones of the Inferior Oolite in the Cotteswolds, on a close comparison of 
species, may have more affinity with the Lincolnshire Limestone than is usually 
supposed. 
1 ©Proe, Geol. Assoc.,’ vol. ix, p. 208, 1886. 
